Fixing clamp for connecting sheets with different expansion properties

ABSTRACT

A fixing clamp for connection of sheets with different expansion properties and is thus installed in a rectangular opening of a support plate. The fixing clamp includes a rectangular baseplate and a threaded sleeve in the center. Transverse webs are bent in the same directions as the threaded sleeve on a front transverse edge. Two clamping legs are bent away from the sleeve, parallel to the baseplate. A further clamping leg is bent upwards on the opposing rear transverse edge in the same direction as the front clamping leg. Spring webs are cut into the baseplate on both sides of the threaded sleeve and bent at an angle in the same direction as the clamping legs. The spring webs are bent with the end regions thereof reaching the baseplate, whereby a separation “A” between the end regions and the transverse webs on the front clamping leg is of such a size that the spring webs extend into the opening when the front clamping legs are situated ont the longitudinal edge of the opening.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention pertains to a mounting clamp for connecting sheets with different expansion properties, wherein a rectangular opening is recessed into the support plate in order to accommodate the mounting clamp such that it can be displaced parallel to the plate edge.

2. Description of Related Art

Mounting clamps of this type are used, for example, in the automobile industry for connecting a fender of plastic to a metallic support plate. Since the plastic fender has a greater coefficient of expansion than the metallic carrier, the mounting element can adapt itself to relative changes in position between the fender and the support plate that are caused by temperature fluctuations, namely because the mounting element is embedded in the oblong hole such that it can be transversely displaced.

Such a mounting clamp of plastic is known from EP 0 799 758 B1. In this case, a base plate that covers the mounting opening is connected to a sliding element that can be inserted into the mounting opening, wherein said sliding element is guided in the opening such that it can be transversely displaced and held in a position of equilibrium by elastic spring elements. The guidance is realized with limbs that are integrally formed onto the longitudinal sides at a spacing that corresponds to the thickness of the fender sheet and that engage behind the edge of the oblong hole. In order to insert the sliding element into the opening, only one limb is integrally formed onto one longitudinal side, wherein this limb can be inserted into a recess of corresponding size in the edge of the opening. When inserting the sliding element, this limb initially needs to be inserted into the recess and then laterally displaced into the mounting position. The mounting clamp that is provided with a through-hole is subsequently held in this mounting position by elastic spring elements braced on the transverse edges of the rectangular opening.

This mounting clamp apparently proved unsuitable for practical application. One reason for this may be that the limb of the sliding element to be inserted can be displaced in the recess on the edge of the rectangular opening depending on the temperature-related compensation movement. This means that the sliding element may ultimately fall out of the opening. The elasticity of the elastic spring elements that are integrally formed onto the lateral edges may also diminish over time such that the clamp is no longer automatically held in the intended position with the subassembly and the completion of the connection becomes more difficult.

The invention consequently is based on the objective of realizing the mounting clamp in such a way that it can be easily inserted into the mounting opening and reliably held therein during all lateral displacements.

SUMMARY OF THE INVENTION

According to the invention, this objective is attained with a mounting clamp with the characteristics disclosed in claim 1. This makes it possible to shape the clamp from a steel sheet billet with simple means and to simultaneously provide the clamp with a threaded sleeve. This also eliminates a special nut required with mounting clamps according to the state of the art.

The insertion of the mounting clamp into the rectangular opening can be easily realized. For this purpose, the clamp is inserted into the opening with its front limb pointing forward, namely, to such a degree that the elevated limb engages behind the edge of the opening and the threaded sleeve moves past the opposite edge of the opening. The clamp is now pressed upward until the rear limb lies in front of the plate edge. The clamp is then displaced until the spring limbs that were previously pressed down spring upward with their ends on the rear edge of the opening and thusly secure the mounting clamp in the installed position.

With respect to the transversely displaceable design of the clamp, it is appropriate if the upwardly bent spring webs are angled in opposite directions on their ends.

Since the rear clamping limbs are spaced apart from the base plate by such a distance that they can be easily pressed on over the plate edge, it is advantageous, according to another characteristic of the invention, if an additional spring limb with the characteristics of claim 2 is formed between the threaded sleeve and the rear clamping limb and embossed with an approximately hemispherically shaped spherical cap. A corresponding depression in the plate edge of the support plate may be assigned to this spherical cap such that the spherical cap is able to snap into said depression in the predetermined installation position of the mounting clamp.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

FIG. 1, a side view of the mounting clamp;

FIG. 2, a top view of the same clamp;

FIG. 3, a perspective representation of a support plate with the rectangular opening viewed from the bottom;

FIG. 4, a perspective representation of the mounting clamp inserted into the opening in the support plate viewed from the top;

FIG. 5, the installation of the clamp into the rectangular opening of the sectionally illustrated support plate; and

FIG. 6, the same support plate with installed mounting clamp and a second sheet to be connected to the clamp.

DETAILED DESCRIPTION OF THE INVENTION

The mounting clamp illustrated in the figures serves for connecting sheets with different expansion properties by utilizing a screw. The clamp consists of a rectangular base plate 1 of spring steel that is provided with a centrally arranged threaded sleeve 2 for screwing in a screw. On the front transverse edge 3 of the base plate 1 which is illustrated in the upper portion of FIG. 1, two transverse webs 5 are bent upward in the same direction as the threaded sleeve 2, and two clamping limbs 6 are then bent away from the sleeve 2 parallel to the base plate 1, wherein a counter limb 7 is integrally formed onto the transverse edge 3 between the two clamping limbs 6. This counter limb 7 is slightly bent initially toward the clamping limbs 6 over a short section and then slightly bent back again, wherein the distance “a” between the bend 8 and the opposing clamping limbs 6 is approximately identical to the thickness “d” of the support plate 15 (see FIG. 5).

Another clamping limb 10 that points in the same direction as the front clamping limbs 6 is bent upward on the rear transverse edge 4 of the base plate 1 via an angled transverse wall 9. This clamping limb 10 initially is slightly bent toward the base plate 1 over a short section 10′ and then steeply bent only from the base plate over a second section 10″. The distance “b” between the bend 11 and the base plate 1 is slightly larger than the distance “a” on the front clamping limbs 6 in this case.

Spring webs 13 are cut off the base plate 1 at both sides of the threaded sleeve 2 along the longitudinal edges 12, wherein these spring webs are obliquely bent upward in the direction of the rear clamping limbs 10, and wherein the end region 14 is bent downward about vertically to the top of the base plate 1. In this case, it needs to be observed that the distance “A” between the end regions 14 and the transverse webs 5 of the front clamping limbs 6 is equal to or slightly smaller than the clear distance “B” between the two longitudinal edges 17 and 18 of the rectangular opening 16 (see FIG. 5).

When installing the mounting clamp into the rectangular opening 16, the clamp initially is obliquely inserted into the opening 16 from the bottom with the front clamping limbs 6 pointing forward as shown in FIG. 5, namely, to such a degree that the clamping limbs 6 are directed beyond the longitudinal edge 17 of the opening 16 and the counter limb 7 is directed underneath the longitudinal edge 17. The clamp is then inserted into the opening 16 until the threaded sleeve 2 moves past the rear longitudinal edge 18 of the opening 16 and the rear clamping limb 10 is still situated in front of the outer plate edge 19. The rear of the clamp is then pressed upward against the force of the spring webs 13 until the rear clamping limb 10 can be displaced over the plate edge 19. As soon as the front transverse web 5 adjoins the longitudinal edge 17 and the rear transverse wall 9 adjoins the plate edge 19, the spring webs 13 that were previously pressed down spring back into their original position and adjoin the rear longitudinal edge 18 with the angled end regions 14 in such a way that the clamp is guided in the opening 16 between the two longitudinal edges 17 and 18 such that it can be longitudinally displaced as indicated by the double arrow “L” (see FIG. 4).

In order to compensate for the play of the rear plate edge 19 between the rear clamping limb 10 and the base plate 1, an additional spring web 21 is punched out of the center of the base plate 1 between the threaded sleeve 2 and the rear clamping limb 10, wherein this additional spring web is slightly bent upward in the same direction as the rear clamping limb 10. On its free springable end 22, an approximately hemispherically shaped spherical cap 23 is embossed in the direction of the clamping limb 10. This spring web 21 holds the clamp on the plate edge 19 without play in the region of the rear clamping limb 10.

A corresponding depression 24 preferably is arranged in the plate edge 19 in the predetermined installation position of the clamp as shown in FIG. 3, wherein the spherical cap 23 is able to elastically snap into this depression such that the clamp is positively held in this position. However, the spherical cap 23 is able to snap out of the depression 24, and the mounting clamp is able to yield in the direction of the arrow “L” if expansion forces become effective.

The invention has been described in an illustrative manner. It is, therefore, to be understood that the terminology used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Thus, within the scope of the appended claims, the invention may be practiced other than as specifically described. 

1. Mounting clamp for connecting sheets with different expansion properties, wherein a rectangular opening (16) is recessed into the support plate (15) in order to accommodate the mounting clamp such that it can be displaced parallel to the plate edge (19), characterized by the fact that the mounting clamp consists of a rectangular base plate (1) of spring steel with a centrally arranged threaded sleeve (2) and with clamping limbs (6,10) that are integrally formed onto both transverse edges (3,4) and point in the same direction, wherein the clamping limb (6) on the front transverse edge (3) can be inserted into the opening (16) in the support plate (15) and is clamped in position on its rear side, and wherein the clamping limb (10) on the opposite rear transverse edge (4) can simultaneously be clamped in position on the plate edge (19) from outside, and by the fact that spring webs (13) that are cut into the base plate (1) on both sides of the threaded sleeve (2) are obliquely bent upward in the same direction as the clamping limb (6) and are bent downward approximately vertically in the end regions (14) to the top of the base plate (1), wherein the distance “A” between the end regions (14) and the transverse webs (5) of the front clamping limb (6) is equal to or slightly smaller than the clear distance “B” between the two longitudinal edges (17) and (18) of the rectangular opening (16).
 2. Mounting clamp according to claim 1, characterized by the fact that an additional spring limb (21) is punched out of the middle of the base plate (1) between the threaded sleeve (2) and the rear clamping limb (10), and by the fact that the additional spring limb is bent upward in the same direction as the rear clamping limb (10) and an approximately hemispherically shaped spherical cap (23) is embossed on its free springable end (22) in the direction of the clamping limb (10).
 3. Mounting clamp according to claim 2, characterized by the fact that a corresponding depression (24) in the plate edge (19) is assigned to the spherical cap (23), wherein the spherical cap (23) snaps into said depression in the predetermined installation position of the mounting clamp. 